I think the challenge we had personnel-wise during the Parcells era was that the cupboard was so incredibly bare when he got here. That guys like Ferguson and Richie Anderson and Anthony Henry can now be looked at as "meh" signings is a testament to how far we've come since then. But I think the sad truth is that those guys were tremendous upgrades over what we were sporting pre-Parcells.
Who did a guy like Henry even replace? Mario Edwards or someone of a similar ilk?
I look at 2003-06 as the first phase of our oganizational restructuring. I don't think it can be argued that we were among the worst-five-run teams in football from about 1997-2002. So we had a lot of bad things to overturn.
I look at 06-present (I see 06 as overlapping both phases as midway through the season is when Romo was introduced, changing everything) as the second phase that took us from taking a bad team to a team capable of contending for the playoffs, to a team expected to make the playoffs and capable of contending for something much bigger.
There were a lot of things Parcells did that I disagree with, and I'm actually not all that sad we now have Phillips instead (never thought I'd say that). But he was instrumental in removing us from the league's doldrums, and I think even relatively "meh" signings like Richie Anderson played a critical role in doing that.
(Side note: I think most of Parcells' flops were the no-name ex-Jets he brought in. Eric Ogbogu and others who were mostly training camp fodder or bottom feeders on the roster. But I think their presence was more for reinforcing Parcells' beliefs than their ability.)